/*
 * Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.org.apache.bcel.internal;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import com.sun.org.apache.bcel.internal.classfile.JavaClass;
import com.sun.org.apache.bcel.internal.util.*;
import java.io.*;

/**
 * The repository maintains informations about class interdependencies, e.g.,
 * whether a class is a sub-class of another. Delegates actual class loading
 * to SyntheticRepository with current class path by default.
 *
 * @see com.sun.org.apache.bcel.internal.util.Repository
 * @see com.sun.org.apache.bcel.internal.util.SyntheticRepository
 *
 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 */
public abstract class Repository {
    private static com.sun.org.apache.bcel.internal.util.Repository _repository = SyntheticRepository.getInstance();

    /** @return currently used repository instance
     */
    public static com.sun.org.apache.bcel.internal.util.Repository getRepository() {
        return _repository;
    }

    /** Set repository instance to be used for class loading
     */
    public static void setRepository(com.sun.org.apache.bcel.internal.util.Repository rep) {
        _repository = rep;
    }

    /** Lookup class somewhere found on your CLASSPATH, or whereever the
     * repository instance looks for it.
     *
     * @return class object for given fully qualified class name, or null
     * if the class could not be found or parsed correctly
     */
    public static JavaClass lookupClass(String class_name) {
        try {
            JavaClass clazz = _repository.findClass(class_name);

            if (clazz == null) {
                return _repository.loadClass(class_name);
            } else {
                return clazz;
            }
        } catch (ClassNotFoundException ex) {
            return null;
        }
    }

    /**
     * Try to find class source via getResourceAsStream().
     * @see Class
     * @return JavaClass object for given runtime class
     */
    public static JavaClass lookupClass(Class clazz) {
        try {
            return _repository.loadClass(clazz);
        } catch (ClassNotFoundException ex) {
            return null;
        }
    }

    /** @return class file object for given Java class.
     */
    public static ClassPath.ClassFile lookupClassFile(String class_name) {
        try {
            return ClassPath.SYSTEM_CLASS_PATH.getClassFile(class_name);
        } catch (IOException e) {
            return null;
        }
    }

    /** Clear the repository.
     */
    public static void clearCache() {
        _repository.clear();
    }

    /**
     * Add clazz to repository if there isn't an equally named class already in there.
     *
     * @return old entry in repository
     */
    public static JavaClass addClass(JavaClass clazz) {
        JavaClass old = _repository.findClass(clazz.getClassName());
        _repository.storeClass(clazz);
        return old;
    }

    /**
     * Remove class with given (fully qualified) name from repository.
     */
    public static void removeClass(String clazz) {
        _repository.removeClass(_repository.findClass(clazz));
    }

    /**
     * Remove given class from repository.
     */
    public static void removeClass(JavaClass clazz) {
        _repository.removeClass(clazz);
    }

    /**
     * @return list of super classes of clazz in ascending order, i.e.,
     * Object is always the last element
     */
    public static JavaClass[] getSuperClasses(JavaClass clazz) {
        return clazz.getSuperClasses();
    }

    /**
     * @return list of super classes of clazz in ascending order, i.e.,
     * Object is always the last element. return "null", if class
     * cannot be found.
     */
    public static JavaClass[] getSuperClasses(String class_name) {
        JavaClass jc = lookupClass(class_name);
        return (jc == null ? null : getSuperClasses(jc));
    }

    /**
     * @return all interfaces implemented by class and its super
     * classes and the interfaces that those interfaces extend, and so on.
     * (Some people call this a transitive hull).
     */
    public static JavaClass[] getInterfaces(JavaClass clazz) {
        return clazz.getAllInterfaces();
    }

    /**
     * @return all interfaces implemented by class and its super
     * classes and the interfaces that extend those interfaces, and so on
     */
    public static JavaClass[] getInterfaces(String class_name) {
        return getInterfaces(lookupClass(class_name));
    }

    /**
     * Equivalent to runtime "instanceof" operator.
     * @return true, if clazz is an instance of super_class
     */
    public static boolean instanceOf(JavaClass clazz, JavaClass super_class) {
        return clazz.instanceOf(super_class);
    }

    /**
     * @return true, if clazz is an instance of super_class
     */
    public static boolean instanceOf(String clazz, String super_class) {
        return instanceOf(lookupClass(clazz), lookupClass(super_class));
    }

    /**
     * @return true, if clazz is an instance of super_class
     */
    public static boolean instanceOf(JavaClass clazz, String super_class) {
        return instanceOf(clazz, lookupClass(super_class));
    }

    /**
     * @return true, if clazz is an instance of super_class
     */
    public static boolean instanceOf(String clazz, JavaClass super_class) {
        return instanceOf(lookupClass(clazz), super_class);
    }

    /**
     * @return true, if clazz is an implementation of interface inter
     */
    public static boolean implementationOf(JavaClass clazz, JavaClass inter) {
        return clazz.implementationOf(inter);
    }

    /**
     * @return true, if clazz is an implementation of interface inter
     */
    public static boolean implementationOf(String clazz, String inter) {
        return implementationOf(lookupClass(clazz), lookupClass(inter));
    }

    /**
     * @return true, if clazz is an implementation of interface inter
     */
    public static boolean implementationOf(JavaClass clazz, String inter) {
        return implementationOf(clazz, lookupClass(inter));
    }

    /**
     * @return true, if clazz is an implementation of interface inter
     */
    public static boolean implementationOf(String clazz, JavaClass inter) {
        return implementationOf(lookupClass(clazz), inter);
    }
}
